Pension and Other Postretirement Benefits (Table)

3 Months Ended

Jun. 30, 2011

Pension Plans, Defined Benefit [Member]

Defined Benefit Plan Disclosure [Line Items]

Net Pension Cost for the Schlumberger Pension Plans and US Postretirement Medical Plan

	(Stated in millions)
	Second Quarter												Six Months
	2011						2010						2011						2010
	US			Int’l			US			Int’l			US			Int’l			US			Int’l
Service cost — benefits earned during period	$	14		$	17		$	13		$	10		$	30		$	34		$	28		$	24
Interest cost on projected benefit obligation		37			57			35			51			75			113			71			103
Expected return on plan assets		(42	)		(71	)		(47	)		(57	)		(85	)		(141	)		(95	)		(115	)
Amortization of prior service cost		3			30			1			29			6			61			2			57
Amortization of net loss		22			8			15			5			44			16			31			10
	$	34		$	41		$	17		$	38		$	70		$	83		$	37		$	79

Postretirement Medical Plan [Member]

Defined Benefit Plan Disclosure [Line Items]

Net Pension Cost for the Schlumberger Pension Plans and US Postretirement Medical Plan

	(Stated in millions)
	Second Quarter						Six Months
	2011			2010			2011			2010
Service cost — benefits earned during period	$	5		$	6		$	12		$	11
Interest cost on accumulated postretirement benefit obligation		15			14			29			29
Expected return on plan assets		(5	)		(2	)		(10	)		(3	)
Amortization of prior service cost		(3	)		(5	)		(6	)		(10	)
Amortization of net loss		3			2			6			6
	$	15		$	15		$	31		$	33